Vision deterioration in type 2 diabetes tied to smoking, severe hypoglycemia
Adults with type 2 diabetes are at greater risk for vision loss if they have smoked, had an episode of severe hypoglycemia or an elevated urinary albumin-to-creatinine ratio, according to findings published in the Journal of Diabetes and its Complications.
“Smoking, severe hypoglycemia and higher urinary albumin-to-creatinine ratio were independently associated with vision loss in community-dwelling people with type 2 diabetes. All are potentially modifiable risk factors,” Timothy Davis, DPhil, professor in the faculty of health and medical sciences and internal medicine at the University of Western Australia in Perth, Australia, and colleagues wrote. “Smoking cessation strategies and optimal cardiometabolic risk factor management, including blood glucose-lowering regimens that minimize hypoglycemia, appear important in preventing the loss of vision associated with type 2 diabetes.”
Davis and colleagues conducted Bailey Lovie chart tests of visual acuity at baseline and every 2 years in 882 adults with type 2 diabetes from the Fremantle Diabetes Study Phase II (mean age, 65.1 years; 37.8% women). The researchers also collected data on demographics, lifestyle habits and medical history at each visit, which took place during a median follow-up time of 4.1 years. The researchers also collected blood and urine samples, which were used to confirm urinary albumin-to-creatinine ratios.
Among the entire cohort, 0.9% of participants developed vision impairment, or a visual acuity score of greater than 6/19 or 6/48 or lower, at 4 years, and 2.9% of participants experienced a loss in vision. Researchers also found that visual acuity was better in 1.9% of participants at 4 years, although this was usually due to intraocular lens procedures.
“Those with improved visual acuity were more likely to have had an intraocular lens inserted due to a cataract after baseline,” the researchers wrote.
The odds of vision loss tripled among participants who smoked at any point before baseline vs. participants who did not smoke (OR = 3.17; 95% CI, 1.15-8.76).
“Smoking is a well-recognized risk factor for ocular disease,” the researchers wrote. “Interestingly, ex-smokers did not have significantly higher odds of vision loss compared with nonsmokers in our cohort, which suggests that ocular damage caused by smoking may not be permanent.”
The odds of vision loss were even greater in participants who reported a severe hypoglycemic event vs. participants who did not (OR = 5.59; 95% CI, 1.32-23.61).
“Our data show that a history of severe hypoglycemia increased the odds of subsequent vision loss,” the researchers wrote. “In addition, and perhaps alternatively, severe hypoglycemia requiring health service utilization in people with type 2 diabetes might be a surrogate for long duration disease and relatively poorly controlled diabetes, which could increase the risk of ocular complications leading to impaired vision.”
The odds of vision loss rose for every 1 U rise in urinary albumin-to-creatinine ratio (OR = 1.42; 95% CI, 1.09-1.84), with the researchers noting “it is possible that urinary albumin-to-creatinine ratio is a surrogate marker of a variety of ocular diseases with shared risk factors such as poor metabolic control, which have implications for vision.” – by Phil Neuffer
Disclosures: The authors report no relevant financial disclosures.